In Reply: Dr Buccelletti makes some incorrect
assertions that result in a misleading interpretation. It is inappropriate
to use a prior distribution that assumes no expectation of benefit (which
is the assumption of a noninformative prior). No investigator initiates a
trial without prior expectations, and in this case, we expected reviparin
to be beneficial based on a meta-analysis of previous trials of low-molecular-weight
heparin vs placebo, albeit on a moderate number of patients, which indicated
a reduction in myocardial reinfarction (OR, 0.54; 95% CI, 0.33-0.91) and a
nonsignificant reduction in deaths (OR, 0.91; 95% CI, 0.59-1.39).1 If we use a prior distribution of benefit in the moderate
range (10%, 15%, or 20% RR reduction), the mid-point of the posterior estimate
after CREATE is 13.7%, 14.1%, and 14.5%, respectively. In this case, both
the frequentist and Bayesian approaches provide similar estimates of the benefits
of reviparin. Comparison of the relative effect on reductions in mortality
or myocardial reinfarction with the relative effects on bleeding is misleading,
as the event rates of the former are approximately 15 times higher than that
of the latter. The absolute benefits (18 fewer primary outcomes per 1000 patients
treated) of reviparin vastly outweigh the risks (1 more life-threatening bleed
per 1000 patients treated).